Small-size local dry underwater laser welding drainage device and drainage method thereof

Abstract

The application provides a small-size local dry method underwater laser welding drainage device and a drainage method thereof; the drainage device comprises an upper threaded pipe, a lower threaded pipe, a uniform air ring, a connecting module, a drainage cover and a nozzle; the connecting module is provided with a uniform air cavity; a protection air inlet hole is formed in the side wall of the uniform air cavity; the uniform air ring is arranged in the uniform air cavity; a ring-shaped micro gap one is formed between the outer wall of the uniform air ring and the side wall of the uniform air cavity; the protection air is input from the protection air inlet hole, is rectified into uniform annular high-pressure protection air through the ring-shaped micro gap one, and then enters the long straight passage formed by the inner hole of the uniform air ring, the pipe hole of the upper threaded pipe, the pipe hole of the lower threaded pipe and the nozzle jet hole from the space above the uniform air ring; the drainage cover is sleeved outside the lower threaded pipe and extends downward to the outside of the nozzle to form a drainage cavity; and the drainage cover is provided with a drainage air inlet hole. The drainage device effectively generates a local vacuum environment suitable for welding, and has excellent protection for laser welding lenses, and the lenses are not damaged after long-time welding.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of underwater welding, more particularly to a small-size local dry underwater laser welding drainage device and a drainage method thereof. BACKGROUND

[0002] Ocean engineering equipment faces huge structural construction and operation and maintenance needs, and the construction of offshore drilling platforms and offshore oil platforms, the laying of oil pipelines, the repair of nuclear power equipment, etc. cannot be separated from underwater welding and repair technology.

[0003] Current underwater welding technology mainly uses arc welding. Due to the strong cooling effect of water, water pressure, and wet welding area, it is difficult to start the arc, energy is dissipated, and droplet transfer uniformity is poor. Due to the characteristics of laser welding, such as less affected by water pressure, high energy density, and high control precision, laser welding technology is an ideal way for underwater welding. Underwater laser welding has become a research hotspot. However, the drainage effect of existing underwater laser welding devices needs to be improved, and the lens is easily damaged during welding, with a short service life. Therefore, local dry underwater laser welding requires a device that can effectively drain water to create a local vacuum and effectively protect the laser lens. SUMMARY

[0004] To overcome the shortcomings and deficiencies in the prior art, the purpose of the present application is to provide a small-size local dry underwater laser welding drainage device and a drainage method thereof. The drainage device effectively creates a local vacuum environment suitable for welding and has excellent protection for the laser welding lens. The lens is still not damaged after a long time of welding.

[0005] To achieve the above purpose, the present application realizes the technical scheme as follows: a small-size local dry underwater laser welding drainage device, comprising an upper threaded pipe, a lower threaded pipe, a uniform gas ring, a connection module, a drainage cover, and a nozzle.

[0006] The connection module, the upper threaded pipe, the lower threaded pipe, and the nozzle are connected in sequence from top to bottom.

[0007] The connection module is connected with the laser welding device. The connection module is provided with a uniform gas cavity. The side wall of the uniform gas cavity is provided with a protection gas inlet hole for connecting with a protection gas conveying device. The uniform gas ring is arranged in the uniform gas cavity. The outer wall of the uniform gas ring and the side wall of the uniform gas cavity form an annular micro gap one. The uniform gas ring is provided with a uniform gas ring inner hole. The upper threaded pipe is provided with an upper threaded pipe hole. The lower threaded pipe is provided with a lower threaded pipe hole. The nozzle is provided with a nozzle nozzle hole.

[0008] The inner hole of the uniform gas ring, the upper threaded tube hole, the lower threaded tube hole and the nozzle hole are sequentially communicated from top to bottom to form a long straight path for the laser emitted by the laser welding device to pass through; the protective gas is input from the protective gas inlet hole, enters the long straight path formed by the inner hole of the uniform gas ring, the upper threaded tube hole, the lower threaded tube hole and the nozzle hole from the space above the uniform gas ring after being uniformly and rectified into high-pressure annular protective gas by the annular micro gap, and is then output from the nozzle hole.

[0009] The drainage cover is arranged outside the lower threaded tube and extends downward to the outside of the nozzle to form a downwardly open drainage cavity; the drainage cover is provided with a drainage gas inlet hole for connecting with a drainage gas conveying device, and the drainage gas inlet hole is in communication with the drainage cavity.

[0010] The drainage device adopts double-gas drainage; the protective gas is input from the protective gas inlet hole, and then is discharged along the light path through the inner hole of the uniform gas ring, the upper threaded tube hole, the lower threaded tube hole and the nozzle hole after first flushing the lens of the laser welding device; the drainage gas is input from the drainage gas inlet hole, and the drainage gas is discharged from the drainage cavity; the double-gas setting effectively generates a local vacuum environment suitable for welding. The gas path of the drainage device is designed to be narrow, which can ensure small pressure decay and stable airflow, and prevent welding spatter from entering the gas path. The drainage device is cylindrical, and the compact design of small size is suitable for more working conditions.

[0011] Preferably, the upper threaded tube is screwed with the lower threaded tube to realize distance adjustment between the lens of the laser welding device and the nozzle by adjusting the screwing length of the upper threaded tube and the lower threaded tube; the screwing length between the upper threaded tube and the lower threaded tube is locked by a threaded locking ring.

[0012] The upper threaded tube and the lower threaded tube are connected by threads and are provided with a threaded locking ring, so that the drainage device can change the size of the laser light path through threads, and the upper threaded tube and the lower threaded tube are fixed by the threaded locking ring, which effectively expands the variable range of the defocusing amount without increasing the size of the drainage device, and enhances the application range of the drainage device.

[0013] Preferably, the bottom end of the nozzle slightly protrudes below the drainage cover.

[0014] Preferably, the nozzle hole is large at the top and small at the bottom; the minimum diameter of the nozzle hole is greater than the laser spot diameter when welding with the limit defocusing amount.

[0015] The minimum diameter of the nozzle hole is greater than the laser spot diameter when welding with the limit defocusing amount, which can prevent the laser from damaging the nozzle, and a smaller diameter can prevent welding spatter from entering the protective gas path; the nozzle slightly protruding from the drainage cover can make the drainage gas discharge instead of flowing back into the protective gas path.

[0016] Preferably, the annular micro gap one is 2% to 5% of the inner diameter of the gas uniformizing cavity.

[0017] Preferably, the top of the connecting module is provided with a connecting convex ring, and the connecting convex ring is provided with a groove for mounting a sealing ring one.

[0018] Preferably, the upper part of the drainage cover is sealingly connected with the lower threaded pipe, and the drainage cover is provided with a drainage air inlet hole in the area below the sealing connection and forms an annular micro gap two between the outer wall of the lower threaded pipe.

[0019] Preferably, the drainage cover and the lower threaded pipe are connected by bolts, and a sealing ring two is arranged between the drainage cover and the lower threaded pipe to realize sealing.

[0020] A drainage method for the small-size local dry underwater laser welding drainage device is characterized in that: first, the protective gas is introduced from the protective air inlet hole to flush the lens of the laser welding device through the space above the gas uniformizing ring, and then is discharged along the light path through the inner hole of the gas uniformizing ring, the hole of the upper threaded pipe, the hole of the lower threaded pipe and the nozzle hole to generate a drainage effect; then, the drainage gas is introduced from the drainage air inlet hole, and the drainage gas is discharged from the drainage cavity to realize the dry local vacuum formed by the double-gas drainage; after the dry local vacuum is formed, the laser welding device performs laser welding.

[0021] After the laser welding is completed, the laser light of the laser welding device is turned off, and the laser welding head of the laser welding device is cooled; then, the drainage gas delivery is turned off, and finally the protective gas delivery is turned off.

[0022] Preferably, the pressure of the protective gas is slightly higher than that of the drainage gas; the gas backflow is prevented to prevent water droplets or welding splashes from damaging the lens of the laser welding device.

[0023] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0024] 1. The drainage device of the present application adopts double-gas drainage, effectively generates a local vacuum environment suitable for welding, and has excellent protection for the laser welding lens, and the lens is still not damaged after long-time welding, which greatly improves the welding efficiency.

[0025] 2. The drainage device of the present invention has a variable defocus amount; different defocus amounts will have different effects during laser welding. Small defocus amount is suitable for thick plate welding, but the weld width is smaller. Large defocus amount is suitable for thin plate and filler wire welding. The variable defocus amount design effectively expands the scope of application of the present invention.

[0026] 3. The drainage device of the present invention uses annular micro-slit one and annular micro-slit two to rectify the bundled protective gas and drainage gas into a uniform annular high-pressure gas, thereby improving the drainage effect.

[0027] 4. The drainage device of the present invention has a compact design and a small overall size; the small size design makes the device easier to assemble with robotic arms, welding robots, etc., and easier to weld in working conditions with small space; in addition, the small size design also greatly reduces the amount of gas required for drainage. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of the small-sized local dry underwater laser welding drainage device of the present invention;

[0029] Figure 2 This is an exploded view of the small-sized local dry underwater laser welding drainage device of the present invention;

[0030] Figure 3 This is a schematic diagram of the protective gas path of the small-sized local dry underwater laser welding drainage device of the present invention;

[0031] Figure 4 This is a schematic diagram of the drainage gas path of the small-sized local dry underwater laser welding drainage device of the present invention;

[0032] Figure 5 This is a schematic diagram showing the connection between the small-sized local dry underwater laser welding drainage device and the laser welding device of the present invention;

[0033] Among them, 1 is the connecting module, 2 is the upper threaded pipe, 3 is the threaded locking ring, 4 is the drainage and air inlet hole, 5 is the drainage cover, 6 is the nozzle, 7 is the air equalization ring, 8 is the lower threaded pipe, 9 is the connecting convex ring, 10 is the protective air inlet hole, 11 is the sealing ring II, and 12 is the lens of the laser welding device. Detailed Implementation

[0034] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0035] Example

[0036] This embodiment describes a small-sized, locally dry underwater laser welding drainage device, such as... Figures 1 to 5 As shown, it includes an upper threaded pipe 2, a lower threaded pipe 8, an air distribution ring 7, a connecting module 1, a drainage cover 5, and a nozzle 6.

[0037] The connecting module 1, the upper threaded tube 2, the lower threaded tube 8, and the nozzle 6 are connected sequentially from top to bottom; the connecting module 1 is connected to the laser welding device; the connecting module 1 is provided with a gas equalization chamber; the side wall of the gas equalization chamber is provided with a protective air inlet 10 for connection with the protective gas delivery device; the gas equalization ring 7 is set in the gas equalization chamber; an annular micro gap is formed between the outer wall of the gas equalization ring 7 and the side wall of the gas equalization chamber; the gas equalization ring 7 is provided with an inner hole; the upper threaded tube 2 is provided with an upper threaded tube 2 hole; the lower threaded tube 8 is provided with a lower threaded tube 8 hole; the nozzle 6 is provided with a nozzle 6 spray hole.

[0038] The inner hole of the gas equalizing ring 7, the pipe hole of the upper threaded pipe 2, the pipe hole of the lower threaded pipe 8, and the nozzle hole of the nozzle 6 are connected sequentially from top to bottom to form a long straight passage for the laser emitted by the laser welding device to pass through. The protective gas is input from the protective air inlet 10, and after being rectified into a uniform annular high-pressure protective gas through the annular micro gap, it enters from the space above the gas equalizing ring 7 into the long straight passage formed by the inner hole of the gas equalizing ring 7, the pipe hole of the upper threaded pipe 2, the pipe hole of the lower threaded pipe 8, and the nozzle hole of the nozzle 6, and then exits from the nozzle hole of the nozzle 6.

[0039] The top of the connecting module 1 is provided with a connecting protrusion 9; the connecting protrusion 9 is provided with a groove for installing the sealing ring 1. Both the connecting protrusion 9 and the gas equalization ring 7 of the connecting module 1 are higher than the mating surface of the laser welding device, and the connection of the laser welding device is provided with a groove, and the two fit together; the mating point between the connecting module 1 and the laser welding device is provided with the sealing ring 1 to prevent the protective gas from leaking out from the mating point; a certain gap is left between the gas equalization ring 7 and the lens 12 of the laser welding device so that the protective gas can flow normally.

[0040] The upper threaded tube 2 and the lower threaded tube 8 are screwed together to adjust the distance between the lens 12 and the nozzle 6 of the laser welding device by adjusting the screw length of the upper threaded tube 2 and the lower threaded tube 8; the screw length between the upper threaded tube 2 and the lower threaded tube 8 is locked by a threaded locking ring 3.

[0041] The upper threaded tube 2 and the lower threaded tube 8 are connected by threads and equipped with a threaded locking ring 3. This allows the drainage device to adjust the size of the laser optical path through the threads. The threaded locking ring 3 helps to fix the upper threaded tube 2 and the lower threaded tube 8. This effectively expands the range of adjustable defocusing amount without significantly increasing the size of the drainage device, thus enhancing the applicability of the drainage device.

[0042] The preferred value range for the annular micro-slit is 2% to 5% of the inner diameter of the gas equalization chamber. The annular micro-slit can rectify the bundled protective gas into a uniform annular high-pressure protective gas, and then deliver it to the inner hole of the gas equalization ring 7.

[0043] The drain cover 5 is fitted on the outside of the lower threaded tube 8 and extends downward to the outside of the nozzle 6 to form a drain cavity with the opening facing downward; the drain cover 5 is provided with a drain air inlet 4 for connection with the drain air conveying device, and the drain air inlet 4 communicates with the drain cavity.

[0044] Specifically, the upper part of the drain cover 5 is sealed to the lower threaded pipe 8; the drain cover 5 and the lower threaded pipe 8 are connected by bolts, and a sealing ring 11 is provided between the drain cover 5 and the lower threaded pipe 8 to achieve a seal. In the area below the sealed connection, the drain cover 5 is provided with a drain air inlet 4, which forms an annular micro-gap 2 between the drain cover 5 and the outer wall of the lower threaded pipe 8; the drain air is input from the drain air inlet 4, and is rectified into a uniform annular high-pressure drain air through the annular micro-gap 2 to achieve circumferential uniformity of the drain air pressure in the drain chamber.

[0045] The bottom of nozzle 6 protrudes slightly below the drain cover 5. This slight protrusion allows drainage gas to escape, preventing it from flowing back into the protective gas path. The nozzle 6 orifice is wider at the top and narrower at the bottom; the minimum diameter of the nozzle 6 orifice is larger than the laser spot diameter when welding with the ultimate defocusing amount. This larger orifice diameter prevents laser damage to nozzle 6, while the smaller diameter avoids weld spatter entering the protective gas path.

[0046] The drainage device employs a dual-air-path drainage system. Shielding gas enters through the shielding inlet 10, passes above the gas equalization ring 7, first scouring the lens 12 of the laser welding device, and then exits along the optical path through the inner hole of the gas equalization ring 7, the hole of the upper threaded tube 2, the hole of the lower threaded tube 8, and the nozzle 6. Drainage gas enters through the drainage inlet 4 and exits from the drainage chamber. This dual-air configuration effectively creates a localized vacuum environment suitable for welding. The narrow air path design of the drainage device ensures minimal pressure attenuation, stable airflow, and prevents welding spatter from entering the air path. The cylindrical shape and compact design of the drainage device make it suitable for a wider range of working conditions.

[0047] The drainage method of the above-mentioned small-size local dry underwater laser welding drainage device is as follows: First, the protective gas is introduced through the protective gas inlet 10 and passes through the space above the gas equalization ring 7 to first flush the lens 12 of the laser welding device. Then, it is discharged along the optical path through the inner hole of the gas equalization ring 7, the pipe hole of the upper threaded tube 2, the pipe hole of the lower threaded tube 8, and the spray hole of the nozzle 6, thus producing a drainage effect. After that, the drainage gas is introduced through the drainage gas inlet 4 and discharged from the drainage chamber, realizing the dual drainage of protective gas and drainage gas to form a dry local vacuum. After the dry local vacuum is formed, the laser welding device performs laser welding.

[0048] After laser welding is completed, turn off the laser output of the laser welding device and wait for the laser welding head of the laser welding device to cool down; then turn off the drainage gas supply, and finally turn off the protective gas supply.

[0049] The protective gas pressure is slightly higher than the drain gas pressure; this prevents backflow of gas from causing water droplets or welding spatter that could damage the lens 12 of the laser welding device.

[0050] The drainage device of this invention can effectively drain water at a depth of 30m, creating a local vacuum and effectively protecting the laser welding head lens; its small-size variable defocus design adapts to various welding conditions.

[0051] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A small-sized, locally dry underwater laser welding drainage device, characterized in that: Includes upper threaded pipe, lower threaded pipe, air distribution ring, connecting module, drainage cover, and nozzle; The connecting module, upper threaded pipe, lower threaded pipe and nozzle are connected sequentially from top to bottom; The connecting module is connected to the laser welding device; the connecting module is provided with a gas equalization chamber; the side wall of the gas equalization chamber is provided with a protective air inlet for connection with the protective gas delivery device; a gas equalization ring is provided in the gas equalization chamber; an annular micro gap is formed between the outer wall of the gas equalization ring and the side wall of the gas equalization chamber; the gas equalization ring is provided with an inner hole; the upper threaded tube is provided with an upper threaded tube hole; the lower threaded tube is provided with a lower threaded tube hole; the nozzle is provided with a nozzle spray hole. The inner hole of the gas equalizing ring, the upper threaded pipe hole, the lower threaded pipe hole, and the nozzle nozzle are connected sequentially from top to bottom to form a long straight passage for the laser emitted by the laser welding device to pass through; the protective gas is input from the protective gas inlet, rectified into a uniform annular high-pressure protective gas through the annular micro gap, and then enters the long straight passage formed by the inner hole of the gas equalizing ring, the upper threaded pipe hole, the lower threaded pipe hole, and the nozzle nozzle from the space above the gas equalizing ring, and then outputs from the nozzle nozzle; The drainage cover is fitted over the outside of the lower threaded tube and extends downward to the outside of the nozzle to form a drainage chamber with the opening facing downward; the drainage cover is provided with a drainage air inlet for connection with the drainage air conveying device, and the drainage air inlet communicates with the drainage chamber. The upper threaded tube and the lower threaded tube are screwed together to adjust the distance between the lens and the nozzle of the laser welding device by adjusting the screw length of the upper threaded tube and the lower threaded tube; the screw length between the upper threaded tube and the lower threaded tube is locked by a threaded locking ring. The value range of the annular micro-slit is 2% to 5% of the inner diameter of the air-uniform cavity; The upper part of the drainage cover is sealed to the lower threaded pipe; the area below the sealed connection of the drainage cover is provided with a drainage air inlet hole, and an annular micro gap two is formed between the drainage cover and the outer wall of the lower threaded pipe; the drainage air is input from the drainage air inlet hole, and is rectified into a uniform annular high-pressure drainage air through the annular micro gap two, so as to achieve circumferential uniform drainage air pressure in the drainage chamber.

2. The small-sized local dry underwater laser welding drainage device according to claim 1, characterized in that: The bottom of the nozzle protrudes slightly below the drain cover.

3. The small-sized local dry underwater laser welding drainage device according to claim 1, characterized in that: The nozzle orifice is larger at the top and smaller at the bottom; the minimum diameter of the nozzle orifice is greater than the diameter of the laser spot when welding with the ultimate defocusing amount.

4. The small-sized local dry underwater laser welding drainage device according to claim 1, characterized in that: The top of the connecting module is provided with a connecting protrusion ring; the connecting protrusion ring is provided with a groove for installing a sealing ring.

5. The small-sized local dry underwater laser welding drainage device according to claim 1, characterized in that: The drainage cover and the lower threaded pipe are connected by bolts, and a sealing ring is provided between the drainage cover and the lower threaded pipe to achieve a seal.

6. A drainage method for the small-sized local dry underwater laser welding drainage device as described in claim 1, characterized in that: First, the protective gas is introduced through the protective gas inlet and passes through the space above the gas equalization ring to flush the lens of the laser welding device. Then, it is discharged along the optical path through the inner hole of the gas equalization ring, the upper threaded pipe hole, the lower threaded pipe hole, and the nozzle nozzle, creating a drainage effect. Next, the drainage gas is introduced through the drainage gas inlet and discharged from the drainage chamber, achieving dual drainage of protective gas and drainage gas to form a dry local vacuum. After the dry local vacuum is formed, the laser welding device performs laser welding. After laser welding is completed, turn off the laser output of the laser welding device and wait for the laser welding head of the laser welding device to cool down; then turn off the drainage gas supply, and finally turn off the protective gas supply.

7. The drainage method according to claim 6, characterized in that: The protective gas pressure is slightly higher than the drain gas pressure.

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